DEEP-SEA RESEARCHES. 95 



fact, already offered by the French physicist, Pouillet, and 

 also by the Russian physicist, Lcnz, with whose expositions 

 of it Dr. Carpenter afterwards became acquainted, though 

 they had not given any precise indication of the forces 

 which would keep up the movement. It had failed to win 

 acceptance, and the current doctrine on the subject was 

 that of Sir John Herschel. 



With indefatigable industry, Dr. Carpenter set himself 

 to establish his own conception, as he hoped, beyond refu 

 tation. In papers before scientific societies, in private 

 discussions, in popular lectures, in magazine articles, he 

 reasoned and expounded ; he urged fresh illustrations ; he 

 met and overcame unexpected difficulties. The facts ac 

 cumulated in subsequent expeditions, and the masterly 

 combinations in which he arranged them, at length began 

 to produce the desired effect. In a letter, written only a 

 month before his death, in 1871, Sir John Herschel ac 

 cepted the new teaching, which also won the sanction of 

 such distinguished authorities as Sir William Thomson and 

 the Astronomer Royal. 



The second suggestion was due to Professor Wyville 

 Thomson. The animals brought up alive from the chalk- 

 like deposit then in progress over what the temperature- 

 soundings proved to be a relatively warm area, distinguished 

 from a cold area at no great distance, presented many 

 points of most interesting relationship to the Fauna of the 

 Cretaceous period. Was it not possible, then, surmised 

 Professor Thomson, that the deposit of Globigcrina-mud 

 had been going on, over some part or other of the North- 

 Atlantic sea-bed, from the Cretaceous epoch to the present 

 time? Might we not, indeed, be said to be, in one sense, 

 still living in the Cretaceous epoch? 



To the solution of these and other problems generated 

 by the first cruise, successive expeditions were devoted. 



